Just wanted to report I have the same experience as rlprlp.
Windows XP, SP2 updated, 15 Gb of stuff on C drive.
I updated SAS two days ago (used built in updater), ran a full scan on C drive, and finally stopped it at 3 hours 10 minutes. The previous version only took about 1 hour 20 minutes.
Thought I might have had a bad update, so I snagged the executable from SAS website, deleted SAS from computer (used XP's 'Add or Remove Progam', manual searches for all SAS folders, 3 different registry cleaners.)
Installed fresh with the executable, started full scan and went on about my day. Finally had to stop scan at a little over 6 hours. 'File items' count was over 100,000.
Of note while checking the scan occasionally, it was moving along as fast as the previous good version of SAS, but noticed it eventually scanned the same folders again and again.
Anyway, I applied rlprlp's tip of unchecking "Use Direct Disk Access" (thanks for that, rlprlp!) and got a full scan done in 40 minutes. 'File items' count was, I think, a little over 17,000.
Just wanted to add my 2 cents. That is an impressive speed reduction put into this new version of SAS. Outstanding work.